Smellting help!

[Davent]

What have I done!!!??

I had a 38 gram bar, all shiny and gold, I need the injectors done in my hilux, so decided to add some more sub grammars to bring it up to 80 odd grams, then sell.
But something has gone terribly wrong.
I know the gold is good @ 92% but it's come out looking like lead.
I re did it again, same result.
Only added two tea spoons of borax, nothing else.
WhT Have I done wrong. Melt temp was 1150.

 

[Big Johno]

Im not sure mate, done something similar last year with an ounce of grammars and got the same result. Im thinking it is the flux that brings the ***** to the surface.
Get some silver polish and give it a try on a small area. Im planning to give mine a blast in a wet blasting cabinet next week, the wet blasting with glass beads or soda doesn't remove any metal iso will see what happens. Just think, all those beautifull shining gold nuggies looking like a bar of ***** layful:

 

[Davent]

I just put it in ally brite,
See what happens...... 8.(

 

[XLOOX]

I know this is no help Davent but when I was briefly in Peko-Wallsend Warrego NT in late 80s we sometimes had variable coloured bars that looked like yours, even though the colour on the strake table was golden. It was originally believed to be due to higher silver content i ie electrum but the analysis didnt really reflect that and the diagram below shows that it would have to be closer to 70% gold/30% silver to be pale.

In the end I think it was put down to more impurities than the flux could handle.

Good news is that if you are selling to a refiner they wont care what the bar looks like. 92 % gold is 92% gold to them.

 

[Goldfreak]

Sorry Davent. Its worth nothing. Please send it to me. I will even pay the postage for you because I am such a nice guy layful: seriously though great work finding enough gold to make bars like that :Y: I have only found enough to maybe make a small button.

 

[Davent]

Goldfields, no worries can post to you, however, post is expensive from Darwin, somewhere around $5000!

 

[silver]

Cmon Dave..... lookin like someones been painting lead and havin a lend of ya !

My moneys on ya mate bein the culprit
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....................... :cloudy: :cloudy: :cloudy: :cloudy:
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8.( 8.( 8.( :goldnugget:

 

[wiley coyote]

Hi Davent. Try heating the ingot until it's really hot , then lower it into a container of hydrochloric acid. This boils off the external coating of impurities on it. Each time you do it, the outer layer of gold becomes purer, and should become brighter. I was told this is a way of getting a better reading on a gold testing machine as it only reads the outer layer, which is now purer. Tie the ingot to about a metre of wire, with a metre long stick on the other end. This keeps you away from the reaction of the acid when the hot ingot hits it. Be careful. wiley.

 

[wiley coyote]

Here's 2 I melted down. they were both 31.1 grams before melting. These were dunked about 12 times to make them purer. wiley.

 

[Davent]

Thanks Wiley! I will give it a go tomorrow !

 

[Davent]

Melted it again a few more times, and in the end, we drilled into it to have a peek.
It was very silvery inside, so it seems that a few of my sub grammars were a long way from the 92% I thought it was.
Now have had a good look through my nuggets and have found a few that are lighter in colour than the rest, so that's the problem. Any way, will send it away and see what I get for it, it weighed about 75 grams in the end.

 

[Goldfield Joe]

I wouldn't worry about it Dave. Whenever I sell gold, my buyer melts it all down together, small nuggets & scrap gold (9ct etc). Each time the ingot comes out looking like yours. Then we very lightly sand one side with ultra fine paper to buff it a bit and then he tests it with the XRF machine which is the most accurate.

With this method I have never been disappointed with the outcome $$ wise.

Your gold ingot will still be very high purity I reckon 21ct +.

If you have a buyer up there who uses an XRF machine you will get the most accurate outcome.

 

[dinger]

Hi Dave, have a look on u/tube at mbmmllc (Jason) some good videos on smelting gold, use of various flux etc.
Cheers

 

[20x]

Back when i was selling sluiced gold the xrf said it was 20% gold. I still got the full price per gram..

 

[Davent]

Will keep my dirty panned fines separate from from now on.

BTW, selling two of my best nuggets. If anyone knows some one interested in some unique NT nuggets, they can see them here and contact me directly.

Thanks.

180 grams

Same nugget side on.

Cheers Dave.

 

[Bush Turkey]

Nice spec awesome find ! That would have given ya a grin or three. Good work :Y:

 

[Big Johno]

Bugger WA next year , NT here I come :money: layful:

 

[Glenn01]

How's the bar looking now? Or do you think you will just sell to a refinery?

 

[Davent]

Looks the same, will send it off to becks as is, it's 75grams or so, so will still get some coin for a new set of BF Goodrich.
On that, I got 5 years out of my last set, and they have come down in price about $20 a tyre. That's something that does not happen often!

 

[Glenn01]

Is becks better than the Perth mint to sell gold?